Typically, for a plumbing fixture (e.g., a faucet, a tub spout, a shower head), a valve body conveys water flowing from a main water source to a desired destination (e.g., a sink, a tub, a basin). The valve body generally has two water inlet passages through which cold water and hot water from the main water source can respectively flow. The valve body also has a water outlet passage through which the cold water, the hot water or a mixture of the cold and hot water can be discharged to an outlet portion of the plumbing fixture (e.g., a spout). In a one-handle version of the valve body, the valve body has a cavity for receiving a valve cartridge which allows a user to control the flow rate and the temperature of the water flowing through the water inlet passages to the water outlet passage using a single valve actuating mechanism.
One type of (conventional) valve cartridge is a structural assembly including a housing in which two or more disks, plates or the like are disposed. The disks are generally made of a hard material (e.g., ceramic or metal). At least one of the disks (i.e., a fixed disk) is fixed relative to the housing. Another of the disks (i.e., a movable disk) is disposed above the fixed disk and is movable relative to the fixed disk. The valve cartridge includes the actuating mechanism that is directly or indirectly connected at one end to the movable disk. Another end of the actuating mechanism extends through an opening in the housing for manipulation by a user. The end of the actuating mechanism extending through the opening in the housing can be connected to a handle, knob or the like to assist the user in operating the valve cartridge.
In a one-handle version of this type of valve cartridge for use in the one-handle version of the valve body, the fixed disk includes two inlet openings (i.e., a cold water inlet opening and a hot water inlet opening) that substantially align with the water inlet passages of the valve body when the valve cartridge is installed in the valve body. Furthermore, the fixed disk includes an outlet opening that substantially aligns with the water outlet passage of the valve body when the valve cartridge is installed in the valve body. The actuating mechanism is connected to the movable disk via a coupling. The actuating mechanism can be pivoted to cause translational movement of the movable disk. The actuating mechanism can be rotated to cause angular movement of the movable disk.
In this manner, the movable disk can assume different positions relative to the fixed disk. In particular, pivoting of the actuating mechanism changes the flow rate of the water from zero to a maximum flow rate, whereas rotation of the actuating mechanism changes the temperature of the water. Accordingly, a one-handle actuating mechanism can control both the flow rate and the temperature of the water flowing through the valve cartridge.
The valve cartridge also includes one or more seals for preventing water from leaking out of the valve cartridge. The seals can be located, for example, below, between and/or above the disks in the valve cartridge. When the valve cartridge is installed in the valve body, a retention nut is generally used to secure the valve cartridge in the valve body. The retention nut engages an installation ledge of the housing of the valve cartridge such that the seals in the valve cartridge are compressed and, thus, apply a loading force to the components (including the disks) in the valve cartridge. Accordingly, the fixed disk and the movable disk are kept in water tight contact after installation of the valve cartridge in the valve body.
Typically, the conventional valve cartridge has structure that limits movement of the actuating mechanism, thereby defining the range of flow rates and/or temperatures of the water flowing through the valve cartridge. The conventional structure used to limit the movement (e.g., pivoting) of the actuating mechanism to define the range of flow rates includes a carrier, the movable disk or a bearing.
A carrier is an element disposed between the actuating mechanism and the movable disk. The carrier functions as the coupling that connects the actuating mechanism to the movable disk. Pivoting of the actuating mechanism results in linear movement of the carrier which, in turn, causes linear movement of the movable disk. An internal portion of the valve cartridge can be used to limit the linear movement of the carrier. For example, the carrier contacting an inner surface of a housing of the valve cartridge can limit the linear movement of the carrier. As a result, the movement of the actuating mechanism and the movable disk are also limited. In this manner, the inner surface of the housing limits the movement of the carrier and, thus, defines the range of flow rates of the valve cartridge.
Similarly, an internal portion of the valve cartridge can be used to limit the linear movement of the movable disk. For example, the movable disk can contact the inner surface of the housing of the valve cartridge. As a result, the movement of the actuating mechanism and the carrier (if present) are also limited. In this manner, the inner surface of the housing limits the movement of the movable disk and, thus, defines the range of flow rates of the valve cartridge.
A bearing (e.g., a journal bearing) disposed in the valve cartridge can also be used to limit the movement of the actuating mechanism to define the range of flow rates of the valve cartridge. The bearing can be a component of the actuating mechanism or some other discrete bearing in the valve cartridge. For example, the actuating mechanism can extend through an opening formed in the bearing so that it contacts opposing sides of the opening to define the range of flow rates.
As noted above, the conventional structure directly or indirectly limits the movement of the actuating mechanism to define the range of flow rates of the valve cartridge. The range of flow rates extends from a minimum flow rate corresponding to the valve cartridge being in a fully off state to a maximum flow rate corresponding to the valve cartridge being in a fully on state. The conventional structure, however, has several drawbacks.
If the carrier or the movable disk contacts the inner surface of the housing to limit the movement of the actuating mechanism and define the range of flow rates of the valve cartridge, the housing can become compromised (e.g., deformed) over time as a result of wear or from excessive loads being transferred from the actuating mechanism to the housing through the carrier or the movable disk. If the housing is compromised in the area of the carrier or the movable disk, the valve cartridge is prone to a failure resulting in leakage of the water flowing through the valve cartridge such that the valve cartridge can be rendered inoperable.
Furthermore, the carrier or the movable disk will contact the housing when the valve cartridge is in the fully on or the fully off position. In the fully on or the fully off position, the carrier or the movable disk can be rotated to adjust the temperature of the water, thereby resulting in increased wear as the carrier or the movable disk rubs against the housing.
Using the bearing to define the range of flow rates of the valve cartridge is also problematic. The bearing represents an additional part that needs to be manufactured, managed and maintained. Accordingly, the bearing increases an overall cost of the valve cartridge. Furthermore, the bearing further complicates the assembly process of the valve cartridge. As an additional part, the bearing introduces additional tolerances into the valve cartridge that can adversely affect the feel of the actuating mechanism during operation of the valve cartridge.
Consequently, there is a need in the art for a valve cartridge having integral structure that forms a stop for the actuating mechanism with a reduced risk of failure in a water flow path of the valve cartridge.